1 /* 2 * Copyright (c) 2016, 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 package jdk.jfr; 26 27 import java.lang.annotation.ElementType; 28 import java.lang.annotation.Retention; 29 import java.lang.annotation.RetentionPolicy; 30 import java.lang.annotation.Target; 31 32 /** 33 * Annotation that signifies that a method in an event class should be used to 34 * filter out events. 35 * <p> 36 * For the method to be valid it must return a {@code SettingControl} and only have one 37 * parameter, which should be a non-abstract subclass of {@link SettingControl} 38 * <p> 39 * The return value of the method specifies whether the event is to be 40 * written to the Flight Recorder system or not. 41 * <p> 42 * Example. 43 * 44 * <pre> 45 * <code> 46 * class HelloWorld extend Event { 47 * 48 * {@literal @}Label("Message"); 49 * String message; 50 * 51 * {@literal @}SettingDefinition; 52 * {@literal @}Label("Message Filter"); 53 * public boolean filter(RegExpControl regExp) { 54 * return regExp.matches(message); 55 * } 56 * } 57 * </code> 58 * </pre> 59 * 60 * For an example of how the setting controls are defined, see 61 * {@link SettingControl}. 62 * 63 * @see SettingControl 64 * 65 * @since 9 66 */ 67 @Retention(RetentionPolicy.RUNTIME) 68 @Target({ ElementType.METHOD }) 69 public @interface SettingDefinition { 70 }